Telephone receiver



J. S. TIMMONS TELEPHONE RECEIVER Filed May 19, 1922 Patented June 3,1924.

JOHN S. TIMMONS, OEF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR T PENN HEADSET COMPANY INCORPORATED, OF PHILADELPHIA, PENNSYLVANIA, A CORPORA- TIONOF PENNSYLVANIA.

TELEPHONE RECEIVER.

Application filed May 19, 1922. Serial No. 562,106.

tioning of the instrument.

It is further desired to provide a telephone receiver of the above typein which I there shall be no exposed terminals and whose conductorsshall be contained within a cord branched inside rather than outside.

of the receiver case, and in which said cord is immovably clamped so asto avoid the necessity for tie cords and preventing the likelihood ofabrasion of the cord or cable insulation.

I further desire to provide a telephone receiver having novel means forclamping its conductor cable in the casing to prevent stress on theterminals and avoid-able chafing of the cable itself, together withnovel means for connecting the conductor wires to the magnet andwindings. Y

These objects and other advantageous ends I attain as hereinafter setforth, refer- -enoe being had, to the accompanying drawings, in which,

ig. '1 is a side elevation of a telephone receiver constructed inaccordance with my invention;

.Fig. 2' is a frontelevation of the receiver casing with the frontmember thereof removed to show the detail arrangement and constructionof the interior parts of the receiver;

Fig. 3 is a transverse vertical section on the line 33, Fig. 2; and

Fig. 4 is a fragmentary vertical sectionof a detail of my invention.

In the above drawings, 1 represents a fiat cylindrical metallic caseclosed on one face and having its free ed p e externally threaded forthe reception of t e face or cover member 2, which is centrallyperforated. Mounted within the casing and substantially concentrictherewith is a magnet 3 of the horse shoe type having mounted betweeneach of its ends and the adjacentinner face of the back of the casingone arm of an L-shaped pole piece 4.

In each case a bolt 5 passes through the rear wall of the casing,through the pole piece and through the'end of the horse shoe magnet andhas mounted upon its inner end a nut 6 which serves to rigidly hold tothe end of the magnet one end of a stiff metallic strip 7. The latterhowever is suitably insulated both from the bolt and from the magnet 3,so that said bolt serves merely as a device for rigidly holding it inlace.

Each of the pole pieces 4 is extend ed at right angles so as to providetwo poles lying substantially parallel and within the s ace defined bythe horse shoe magnet 3.

11 these poles are mounted the windings of a magnet 88, which areconnected together and also respectively connected to the two strips7-7. A suitable sheet metal or equivalent diaphragm 9 is clamped between the free edge or face of the easing 1 and the cover 2 so as to beheld immediately adjacent but suitably spaced away from the adjacentpole pieces 4.

Each of the metallic strips 7 is offset downwardly and then forwardlyadjacent the ends of the horse shoe magnet and each of them has mountedin it'a clamping screw 10 for the reception of a terminal /of one of theconductors 11 leading into a flexible cable 12. These conductors do notleave the cable until is has passed into the casin 1 and for thepurposeof immovably hol ing it in place therein so as to prevent tension beingbrought on the terminals or strips 7 with WhlCh they are associated, -Iprovide a flanged bushing 13 mounted in an opening in said casing andlongitudinally slot this bushing so that it may be contracted bysuitable means. For this purpose it is externally tapered and threadedfor the reception of a suitable nut 14, which after the cable 12 hasbeen inserted, may be set up so as to rigidly clamp the bushing in thecasing wall as well as to tightly clip the cable to the bushing wherebyit is held from possibility of movement.

From. the above description it will be appreciated that when properlyassembled, all the parts of my device are rigidly mountvibration cannotoccur.

ed so that undesirable relative movement or The parts themselves aresimple and substantial in form, lending themselves to convenient andinexpensive manufacture and assembly. The construction is such that thereceiver is efiicient and thoroughl practical under operatingconditions, t e arrangement being such that likelihood of any of itsparts getting out of adjustment or becoming inoperative is reduced to aminimum.

Moreover the bushing 13 and nut 14 cooperate to make a tight joint withthe cable 12' and thus efiectually exclude moisture from the interior\of the instrument.

I claim:

l. The combination in a telephone receiver of a casing; a magnet in thecasing; pole pieces for the magnet; windings on the pole pieces; boltsmounted on the back of the casing and holding the magnet and its polepieces thereto; w1th terminal members mounted on but insulated from saidbolts and electrically connected to the Windings on the ,pole pieces.

2. The combination in a telephone receiver of a casing; an electromagnettherein; bolts mounted in the back of the casing for holding said magnetin place; with tWo terminal strips respectively connected to the ends ofthe magnet winding and rigidly connected to but insulated from saidbolts.

3. The combination in a telephone receiver of a casing; an electromagnettherein; bolts mounted in the back of the easing for holding said'magnetin place; two terminal strips respectively connected to the ends of themagnet winding and rigidly connected to but insulated from said bolts;and a cable extending into the casing and branched inside of the same,the conductors of said cable being respectively connected to saidterminal stri s.

J HN S. TIMMONS.

